Traditionally applied solutions on smaller telescopes (ones with mirror diameters from 8-10 m) consisted of directly fastening hydrostatic feet and linear motors to the node joints of the structure, which made them susceptible to misalignments due to deformations in the structure. These problems have generally been solved by providing the feet with a ball joint. This solution, which already caused problems with the Large Binocular Telescope (LBT), is unviable in the case of new Extremely Large Telescopes with a diameter between 20 and 50 m, due to the fact that it is necessary to find a way to make the large deformations of the structure compatible with the necessary precisions of the mechanism.
In these cases, a system of hydrostatic supports is used, the function of which consists of supporting a rigid and stable structure, placing an oil film between the hydrostatic supports and the surface of the guide on which they slide, in order to allow for the movement thereof with minimal force and to prevent wear.
In patent literature we find documents such as patent US2010329593, in which hydrostatic supports for large structures are described, especially suitable for large telescopes.
Also forming part of the state of the arte are linear motors, which are electric motors in which the stator and rotor are distributed such that instead of producing rotational movement they produce a force in a longitudinal direction. Low acceleration linear motors are appropriate for surface transport and in patent literature there are several examples thereof.